Increasing Use Of CT

Researchers conducted a retrospective review of nuclear medicine, computed tomography (CT), fluoroscopy and plain-film x-ray imaging examinations performed at two hospitals from 1997 through 2006 to determine how often these imaging exams were performed on pregnant women. Data were then compared to the number of infant deliveries per year for that same time period.

The researchers found that the total number of imaging studies performed on pregnant women at their institution increased by 10.1 percent per year, but the number of CT exams increased by 25.3 percent per year. CT delivers a higher amount of radiation than many other radiologic procedures.

"Women should know that imaging is generally safe during pregnancy and is often used to detect potentially life-threatening problems," Elizabeth Lazarus, assistant professor of diagnostic imaging at the Warren Alpert School of Medicine at Brown University said. "However, this study should raise awareness about imaging trends in pregnant patients and help us continue in our efforts to minimise radiation exposure."

The researchers evaluated 5,270 examinations on 3,285 patients. During the ten years of the study, the number of patients imaged per year increased from 237 to 449, and the number of exams per year increased from 331 to 732. This represented an 89 percent increase in patients and a 121 percent increase in examinations over the course of the study. During the same ten years, the number of deliveries only increased seven percent from 8,661 to 9,264. Imaging utilisation rates (exams per 1,000 deliveries) increased 107 percent.

Use of plain-film x-rays increased an average of 6.8 percent per year, and the number of nuclear medicine examinations rose by approximately 11.6 percent annually. Fluoroscopy utilisation increased by 10.6 percent per year, and CT examinations increased by 25.3 percent per year.

Lazarus hopes that increased use of electronic medical records will help physicians and patients keep track of the number and types of imaging tests performed on pregnant women and give proper consideration to alternative imaging tests - such as MRI and ultrasound - that do not expose the patient or foetus to ionising radiation.